Abrasive tool



2, 1950 w. J. MILLER 2,519,687

' IABRASIVE TOOL Filed July 19, 1949 Patented Aug. 22, 1950 ABRASIVETOOL William J. Miller, Philadelphia, Pa.

Application July 19, 1949, Serial No. 105,485

2 Claims.

This invention relates to abrasive tools, and more particularly toholders for abrasive elements especially adapted for cleaning andpolishing the commutators of automobile generators and the like.

The usual method for cleaning and polishing the commutator of agenerator is to hold an abrasive stone against the commutator while itis rotating. On automobile generators the only access to the commutatorwithout removing the generator is through a small inspection opening inthe side of the housing. Usually the generator is mounted in arelatively confined place so that access to the commutator is difiicultand in any event can be had only with a long slender abrasive elementthat is capable of being passed through the generator casing opening.Such long and slender abrasive elements are not satisfactory in usebecause they are easily broken. Moreover, quite a bit of the stone wouldbe unusable due to the length needed to hold the stone at a distancefrom the commutator.

With the foregoing in mind the principal object of the present inventionis to provide a novel abrasive tool which is especially adaptable foruse in cleaning and polishing the commutators of automobile generators.

Another object of this invention is to provide an abrasive tool as setforth which embodies novel features of construction and arrangementwhich permit the selective interchange and replacement of the abrasiveelements.

A further object of this invention is to provide a novel abrasive toolhaving the features and advantages set forth that can be manufacturedcheaply and that is capable of being used over and over again.

These and other objects of the invention and the various features anddetails of the construction and use thereof are hereinafter fully setforth and described with reference to the accompanying drawing in which:

Figure 1 is a view in perspective of an abrasive tool made in accordancewith the present invention.

Figure 2 is a side elevation of a portion of the tool with an abrasiveelement secured therein.

Figure 3 is a plan view of Figure 2.

Figure 4 is a perspective view showing how the tool may be used forcleaning the commutator of a small generator, and:

Figure 5 is a perspective view of one of the abrasive elements.

Referring more particularly to the drawing, reference numeral designatesgenerally an abrasive tool made in accordance with the presentinvention. As shown, the abrasive tool In comprises an elongated slenderbody member or holder II which is provided with a widened and relativelythicker jaw I2 at each end thereof. Formed in each jaw I2 is a T slot ISin which the abrasive elements l4 are adapted to fit. The abrasiveelements M are each provided with a groove [5 formed on opposite sidesthereof which are arranged to receive the ribs l6 that are provided oneach face of the said jaws l2 so that the abrasive elements M can belocked securely into the said jaws l2.

A relatively narrow groove I1 is cut longitudinally in each of the jawsl2 inwardly from the base of the slot l3 so that the edges of the jawsl2 may be tightened upon the abrasive elements l4. Tightening of thejaws l2 together may be accomplished by bolts [8 which are passedthrough the center of the jaws [2 just forward of the mid-portion of thegroove I! and having a suitable nut l9 threaded thereon.

To use the abrasive tool I!) to clean the commutator 20 of a generator2| the inspection opening 22 is first uncovered by removing the coverplate 23 which in this particular embodiment is shown as a split ring.The abrasive tool I!) is then held so as to position the abrasiveelement 14 against the commutator 2!! while it is rotating. Two abrasiveelements is may be secured in the abrasive tool [0, one may berelatively coarse to be used for the rough work and the other relativelyfine to be used for the finishing operation, or brush seaters may beused instead of the abrasive elements I4 to give the brushes 2. trueseat on the commutator 20.

Thus it will be seen that a device of the present invention provides anovel tool for cleaning and polishing the commutators of smallgenerators with substantial ease and rapidity wherein substantially allof the abrasive element may be used and then discarded and replaced by anew element.

While certain embodiments of the invention have been herein illustratedand described, it is not intended that the invention be limited to suchdisclosures and changes and modifications may be incorporated andembodied therein within the scope of the following claims.

I claim:

1. An abrasive tool comprising an elongated slender body portion havingrelatively thicker and wider jaw portions at opposite ends thereof, saidjaws each having an endwise slot extending longitudinally inward of thejaw and. terminating wise slot extending longitudinally inward of thejaw and terminating at its base in a relatively narrow inner slot, saidendwise slot having laterally undercut portions providing inwardlyfacing confronting ribs on the jaw constructedto interlockingly engagean abrasive element received in said jaw, and means passing through thejaw in the narrow inner slot portion thereof to clamp an abrasiveelement securely in said jaw.

WILLIAM J. MILLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,100,951 Brown June 23, 1914-.

FOREIGN PATENTS Number Country Date 122,784 Switzerland Oct. 1, 1927

